Hi @Fess67 ,
You are almost there 🙂
I created the following table to replicate yours (multiple records related to 2 ids):

You will need not only your 'List buckets' action, but also a 'List rows present in a table', and identify the table that you want to update:

After that, you will need only one loop, and it will map the 'value' property from your 'List rows present in a table' action. Inside this loop, you will need a filter array, but at this time, filter the 'List buckets' value. For the filter input, insert the 'value id' property from 'List buckets' in the left side (highlighted in blue), set 'is equal to' in the dropdown (highlighted in green) and insert the 'Bucket' dynamic content from your 'List rows present in a table' in the right side (highlighted in yellow):

Now we will update the Excel file. Enter the details about your Excel table and indicate the 'Key column' as your task id (or as any other column with unique values only). As key value, select the dynamic content of your 'Task Id' from your 'List rows present in a table' action (highlighted in yellow). IN the bucket input, enter the following expression: body('Filter_array')[0]['name']. To insert an expression, open the dynamic content pop up, change it to the 'Expression' tab (highlighted in blue) and enter the expression content into the 'Fx' input (highlighted in pink):

To understand a little more about how to update Excel tables with Power Automate, I recommend you this article, which is part of a series of posts about the integration of both tools: http://digitalmill.net/2023/07/24/inserting-and-updating-data-into-excel-tables-with-power-automate/
After run the flow, this is the output:

If you have any trouble with dynamic contents or expressions, check this article: http://digitalmill.net/2023/07/31/using-dynamic-content-in-power-automate/
Let me know if it works for you or if you need any additional help!
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